It's actually not that bad depending on where your steps are - I just listen to music while I do it. If your steps are super steep probably not the best idea but normal steps you're used to should be ok for most.
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There is a study that shows in times of famine, women with the most muscle mass still had boys even at lower weights.
The theory is that testosterone comes from muscle and more testosterone = more boys. But really, we honestly don't know how it works and it may very well be the case that in times of famine, the women who are able to maintain the most muscle mass because they were in better health/condition or had more food than others (even in a famine, some have more than others). So that is one thing that while we do take into consideration, no need to dwell on overly much.